Here's a quick guide to RSS, which you may have seen mentioned on websites and blogs. (Note: I've written this guide with the complete novice in mind. If you already know what an RSS feed is, think about bookmarking this article in order to refer to it colleagues who are less knowledgeable than you. Thanks!)
What does RSS stand for?
The most commonly accepted answer is 'Really Simple Syndication'.
What does RSS let me do?
It makes it easy to do two things really easily. Firstly, it lets you read the articles on your favourite websites all in one place, using an application called a 'feed reader'. Secondly, as an extension of that, it lets you collate the latest posts from several blogs all in one place. It doesn't have to be only blog posts. It could be latest comments on someone's blog, or their most recent tweets in Twitter, or anything else that has an RSS feed.
Taking the first point, it means that you don't have to traipse from one website to another to check if there is anything new: new stuff will show up in your feed reader automatically.
How do I obtain a feed reader?
Just search for the term 'feed reader' and then find one that suits you. You can have one which is installed on your computer, or one that resides on the web. I prefer the latter, because it means it doesn't matter whether you're sitting at your own computer or not when you feel like checking for new content. Some installed feed readers let you synchronise with a web-based one, meaning that you potentially get the best of both worlds.
Popular feed readers include Bloglines and Google Reader, which are web-based. For other readers, look at this article about feed readers.
Update: since this article was written, Google has decided to discontinue its RSS Reader service. There are plenty of alternatives, however. Check out RSS isn't dead: the best Google Reader alternatives. Read the comments too, as there are suggestions in there as well. Feedly has been cited lots of times in articles. I myself have started to try one called The Old Reader, which seems quite nice.
How do I subscribe to an RSS feed?
If you've installed your feed reader's browser toolbar, you should be able to do so by clicking on 'Subscribe', if the blog or website has been set up to allow this. Otherwise, look for an icon like this: 
and click on it; your feed reader should do the rest. If it doesn't, right-click on the icon and select the menu item which reads 'Copy link location' (or similar), open your feed reader, and then paste the link into the New Subscription box. Don't worry: it's all a lot simpler and quicker than it sounds.
How do I read new articles?
Just open your feed reader and see what, if anything, has been added to the various websites since you last looked.
Conclusion
RSS makes it easy for you to keep up with lots of reading in a shorter period of time than would probably otherwise be the case, because you're not racing all over the internet from site to site.
If you're a teacher, it can also benefit your students. For example, if your school uses a virtual learning environment (VLE) you could set up areas for students to visit where the latest headlines from a range of websites are displayed. That could be used purely for reference, or you could incorporate it into lessons. For example, the first five or ten minutes of each lesson could be spent discussing what's new in the world of hospitality and catering, or in business and finance. At the risk of sounding clichéd, the uses for RSS are limited only by your imagination.
I hope you have found this useful. Feel free to comment on the article.